A previously developed, in-house DOS program for drawing DNA sequences has received considerable use both within the NIH community and more widely. However, based on its inadequacies and numerous requests for a version running on the Macintosh, work has begun preparing a completely new version of DNAdraw for the Macintosh. It will do essentially the same job, i.e., formatting sequence data and drawing highlighted sequences for publication, but it will have a number of significant improvements over the PC version. First, being on the Macintosh and conforming to the standard Macintosh principles, it will be immediately usable, with little or no reference to a manual required. The Macintosh system of menus will make the specification and drawing of highlights extremely simple for the user. In addition it will use the capabilities of the mouse to make interaction with the program much easier than the PC version. There is great emphasis now on finding sequences homologous to a given sequence and producing an alignment of the group. A new feature of the DNAdraw program allows for automatic highlighting to indicate which parts of such sequences are homologous. This is done instantaneously after a short dialog with the user. Since most sequencing laboratories at NIH are now using the Macintosh for their computer support, this new version of DNAdraw should get wide use.